Explanations and comparisons

Reminders

  • Workbook homework due on Thursday

Goals

  • Begin looking at relationships between variables

  • Theoretical Arguments and Hypotheses

  • Elements of a good theory

  • Writing good hypotheses

  • Testing Hypotheses

The goals of research

  • Describing: making generalization about the world

  • Predicting: generating expectations about what will happen in the future

  • Explaining: explaining why things are related.

Explanation is often the toughest to achieve, but also the most desirable because it allows us to do things like make changes to reach a desired outcome.

“Why” questions

  • “Why questions”

    • Why do some eligible voters fail to turn out on election day?
    • What explains variation in gun policies across U.S. states?
    • Why did communist revolutions happen in China and Russia but not Europe or the United States?

Theories

“a logically interconnected set of propositions from which empirical uniformities can be derived” – Robert K Merton

Theories are explanations, assumptions, claims and narratives that provide a set of expectations that link a cause to an effect.

Purely descriptive or predictive analyses don’t necessarily require a theory, but its a key component of explanatory research.

Theoretical Scope

Theories vary in their scope:

  • Early sociologists like Marx, Durkheim, Weber attempted to develop all-encompassing “laws” of political/social/historical change. These are sometimes called “grand theories”
  • Contemporary social sciences are less ambitious, and so its more common to propose “middle-range” theories that seek to explain a smaller number regularities in one area.
    • However, they may draw on “grand theories” either implicitly or explicitly.

Paths to Modernity

What explains differences in the “path to modernity” across different countries during the 20th century?

  • Free markets/Democracy in the U.S. and England

  • Fascism in Germany and Japan

  • Communism in Russia and China

Paths to Modernity

Barrington Moore: Classes have unique and conflicting interests. Conflicts over these interests come to the forefront during industrialization. The outcomes of these class conflicts shape the political and economic system.

Paths to Modernity

  • Fascist states emerge when the landed aristocracy allies with industry to repress the peasantry.

  • Communist states emerge when the middle class doesn’t emerge and peasants revolt.

  • Democracies emerge when the bourgeoisie (middle class) is strong.

Paths to Modernity

  • Moore’s theory borrows assumptions from a (sociological) Marxist grand theory about class conflict

  • He “tests” it by showing how it fits the selected cases.

Paths to Modernity

Good theories can be used and refined to generate a set of empirical expectations about what factors should matter. For instance, we might expect:

  • States with larger agricultural sectors during industrialization to be less democratic today (compared to states with smaller agricultural sectors)

  • States with higher literacy rates during industrialization to be more democratic (compared to states with lower literacy rates)

Good Theories

  • Good theories clearly identify:

    • A dependent variable(s): the outcome to be explained

    • One or more independent variables: the causal factors that determine the DV.

    • A causal mechanism that links these two things.

    • An expectation about the direction of the effect (positive, negative, something more complex)

Good theories

  • Most social science theories are probabilistic instead of deterministic. So we’ll speak in terms of more/less likely or higher/lower.

  • Good theories should generate expectations that can be empirically tested (even if the theory itself can’t be tested)

Causal diagrams

  • Causal diagrams are a way to visualize cause and effect relationships in a theoretical model.

G Cause Cause Outcome Outcome Cause->Outcome

Causal diagrams

  • Nodes indicate variables, and arrows indicate causal relationships.

G Cause Cause Outcome Outcome Cause->Outcome

Causal diagrams

For instance, we might think about a simplified version of Moore’s thesis like this

G Cause Strength of the middle class Outcome Political system Cause->Outcome

Causal diagrams: forks

A “fork” refers to a case where a single cause leads to multiple outcomes of interest.

G Cause Strength of the middle class Outcome Political system Cause->Outcome Outcome2 Wealth Cause->Outcome2

Causal diagrams: collisions

A “collision” happens when two causes “collide” on a single outcome:

G Cause Strength of the middle class Outcome Political system Cause->Outcome Cause2 Culture Cause2->Outcome

Causal diagrams: chains

A chain refers to a scenario where one outcome causes something else, which influences a third thing.

G Cause1 Natural resources Cause Strength of the middle class Cause1->Cause Outcome Political system Cause->Outcome

Theories: voting

Why do people vote?

  • Since politicians generally offer public goods, you can enjoy the benefits of your preferred candidate winning even if you don’t vote

  • Since voting has costs (even though they’re small) free riding can be preferable to actually turning out if the costs outweigh the benefits.

Theories: voting

Pivotal voting

  • Claim: people vote because they expect to sway the election

  • If this is true, then:

-   Turnout should be higher in close elections

-   Turnout should be higher when the electorate is small

-   Turnout will be higher in PR systems where one vote matters more.

Theories: voting

Expressive voting model

  • Claim: people vote to enjoy the expressive benefits

  • If this is true then: ::: incremental

    • People with more extreme beliefs will be more likely to vote

    • Closeness or the size of the electorate shouldn’t matter much

:::

Assessing Theories

  • Theories require simplified representations of a complex reality

  • Utility, not “truth”: theoretical models invariably contain assumptions and they’re probably violated in practice.

George Box: “All models are wrong, but some are useful”

Assessing Theories

  • Consistency
    • Is our theory internally consistent? Does it have a clear logic?
  • Empirical accuracy
    • Do the theories help us understand the world?
    • Are observed realities consistent with the expectations our theory generates?
    • Can we use a theory to make useful predictions about future events?
    • Can the theory adapt in the face of inconsistent findings? (this will happen!)
  • Theories may be more or less useful in certain contexts
    • There’s stronger evidence for the pivotal voter model in small elections and referenda, but other models do a better job explaining national level turnout

Hypotheses

  • Theories give causal explanations for why something effects something else

  • Hypotheses are specific testable implications generated by that theory.

    • Theory: people vote because of expressive benefits

    • Hypothesis: people with more extreme views will be more likely to turn out.

Hypotheses

Components:

  • Unit of analysis

  • Dependent variable

  • Independent variable

  • Direction of the predicted relationship

Good hypotheses inevitably involve comparative language (higher/lower/more/less/increase/decrease/better/worse)

Hypothesis Template

In a comparison of [unit of analysis], those having [one value on the independent variable] will be [more/less] likely to have [one value on the dependent variable] than those having a [different value on the independent variable].

Hypothesis Template

In a comparison of [voters], those having [stronger political views] will be more likely to have [a higher likelihood of turnout] than those having a [weaker views].

  • Unit of analysis: voters

  • IV: strength of political views

  • DV: turnout

  • Relationship: strength increases turnout

Hypothesis Template

In a comparison of [states], those having [a larger middle class during industrialization] will be more likely to have [democracy] than those having a [a smaller middle class].

  • Unit of analysis: states

  • IV: size of the middle class

  • DV: democracy

  • Relationship: middle class increases likelihood of democracy

Hypothesis Template

In a comparison of [survey respondents], those having [higher levels of attention to politics] will be more likely to have [consistent responses] than those having a [lower levels of attention to politics].

  • Unit of analysis: Survey respondents

  • IV: level of attention

  • DV: response consistency

  • Relationship: attention increases consistency

Complex Relationships

Good hypotheses may suggest a more complex set of relationships than just “positive/negative”. They could propose conditional/interactive/curvilinear relationships as well.

The “oil curse”

In a comparison of [countries], those having [higher levels of GDP] will be [more likely to be democratic] compared to [countries with lower GDP], [however, this relationship will not hold for countries that get rich from oil exports.]

Retrospective voting:

In a comparison of [voters], those having [lower levels of attention to politics] will be [more likely to vote for the incumbent when the economy is doing well]. Those having [higher levels of attention to politics] will be [more likely to vote based on policy preferences regardless of the state of the economy]

Bad hypotheses

  • The main determinant of war is the distribution of power in the international system.

  • In comparing individuals, annual income and the level of education are related.

  • Democracies are peaceful. In comparing individuals, some people are more likely to favor the death penalty than others.

Next

  • Testing hypotheses by making comparisons

  • Graphing and describing relationships